Biomedical subjects

R Bonan

Publications and source records attributed to R Bonan.

At least 73 records · Page 4Linked to original sources

PubMed1994

Predictive factors of restenosis after multivessel percutaneous transluminal coronary angioplasty.

To evaluate the rate and predictive factors of restenosis after multivessel percutaneous transluminal coronary angioplasty (PTCA), 122 consecutive patients with multivessel PTCA performed in the same setting were included in a prospective study. Systematic angiographic control at 6 months was performed in 112 patients (92%). Restenosis (increase > 20% and stenosis > 50%) was found in 62 patients (55%) and 82 of 254 segments (32%) were dilated. Statistical analysis identified the number of successfully dilated segments as the only predictor of restenosis by patient (2.4 +/- 0.7 vs 2.0 +/- 0.7; p < 0.03), and the greater degree of residual stenosis as the only predictor of restenosis by lesion (30 +/- 14% vs 23 +/- 12%; p < 0.005). Twenty-two of 62 restenosed patients (35%) were asymptomatic (group 1). Baseline clinical and angiographic characteristics of these patients were similar to those with symptomatic restenosis (n = 40; group 2) and without restenosis (n = 50; group 3). Repeat revascularization for restenosis was used only in symptomatic patients (re-PTCA in 36; bypass surgery in 4). After a mean follow-up of 75 +/- 24 months, clinical status, and rates of cardiac death and myocardial infarction were similar in the 3 groups. Medical care was similar in groups 1 and 3, and higher in group 2. However, the rate of repeat revascularization for progression of disease was similar in the 3 groups (29%). In conclusion, restenosis is a frequent event after multivessel PTCA and is strongly related to the number of successfully dilated segments.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

A pilot, early angiographic patency study using a direct thrombin inhibitor as adjunctive therapy to streptokinase in acute myocardial infarction.

BACKGROUND: The success of streptokinase in acute myocardial infarction is hampered by the high failure rate to achieve early reperfusion. This study evaluates the possible benefit of Hirulog (Biogen, Cambridge, Mass), a direct thrombin inhibitor, as adjunct therapy to streptokinase to enhance early patency and prevent rethrombosis. Heparin has been shown to be of very limited benefits in this setting. METHODS AND RESULTS: Forty-five patients were randomized to Hirulog or heparin (2:1 ratio). Coronary angiography documented a TIMI 2 or 3 flow after 90 minutes in 77% of the patients treated with Hirulog and streptokinase and in 47% of patients treated with heparin and streptokinase (P < .05) and after 120 minutes in 87% and 47% of patients, respectively (P < .01). TIMI 3 flow was established in 77% of patients with Hirulog compared with 40% with heparin (P < .02). The clinical outcome and the bleeding rate was also favorable to Hirulog; no reocclusion was observed at late angiography performed 4.7 days later. CONCLUSIONS: Hirulog in this pilot study significantly improved the early patency rate of the infarct-related artery with a favorable clinical profile. This new direct thrombin inhibitor exhibits promise as adjunctive therapy to thrombolysis.

Coronary Angiography↗

PubMed1994

[Is the quantification of mitral valve involvement by transesophageal echography useful before percutaneous mitral commissurotomy?].

The aims of this study were to determine the value of quantifying mitral valve disease by transoesophageal echocardiography before percutaneous mitral commissurotomy (PMC) and to analyse the incidence of embolic complications during PMC since the introduction of transoesophageal echocardiography. From March 1987 to December 1991, 317 patients with pure or dominant mitral stenosis were selected by Doppler echocardiography to undergo PMC at the Montreal Institute of Cardiology. The clinical features of the first 138 patients (Group I) were the same as those of the last 179 patients (Group 2) who also underwent routine transoesophageal echocardiography the day before the procedure. A thrombus in the left atrial appendage was observed in 8 patients in Group 2 (4.4%). No embolic complications have occurred since the protocol was changed to include routine transoesophageal echocardiography, whereas 4 embolic episodes, 3 of which were fatal, occurred in patients in group 1. The indication of PMC was turned down because of angiographically severe mitral regurgitation which was underestimated by transthoracic echocardiography in 2 patients in Group 1 (1.4%) and in 3 patients in group 2 (1.6%). The mobility, thickness and degree of calcification of the valves were attributed a score from 0-4 at transthoracic and transoesophageal echocardiography. No difference was observed in the scores of mobility (2.3 +/- 0.5 versus 2.3 +/- 0.05, NS) or valve thickness (2.1 +/- 0.4 versus 2.1 +/- 0.4, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

[Electron microscopic comparison of the antithrombotic potential of 2 low osmolality iodine contrast media in percutaneous transluminal coronary angioplasty].

The antithrombogenic potentials of two low osmolality iodine contrast media, ioxaglate (Iox), an ionic product, and iopamidol (Iop), a non-ionic product, were compared in a multicentre, randomised, double-blind study in 64 patients undergoing percutaneous transluminal coronary angioplasty (PTCA) by scanning electron microscopy for the presence of thrombotic material on the guiding catheter (GC) and guide wires (GW). The procedure was strictly standardised: stable angina, type A coronary lesions; aspirin administration (at least 300 mg the day before and on the day of angioplasty); heparinisation (10000 IU at the beginning of the procedure); same GCs (Marathon Baxter 8F), same GWs (Veriflex USCI 0.014). The tips of the catheters and guide wires were scanned by an electronic microscope in a double-blind protocol. The scores for the number of erythrocytes (RBCs), platelets (PLs) and constituted thrombi (THi) were; thickness scored from 0 to 3, the % surface covered and an index of volume combining these two parameters. The clinical and angiographic characteristics of the 2 groups were strictly comparable. The time that the GCs and GWs were in the circulation were 30.0 +/- 2.3 vs 32.6 +/- 3.0 minutes for the former, and 18.6 +/- 1.8 vs 17.1 +/- 1.4 minutes for the later in the Iox and Iop groups, respectively (NS). An angiographic filling defect was not observed in any of the patients in the Iox group and in 4 patients (13%) in the Iop group (NS). The number of thrombotic elements observed on the GCs (RBCs, PLs, THi) was negligible in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗

PubMed1993

A comparison of directional atherectomy with balloon angioplasty for lesions of the left anterior descending coronary artery.

BACKGROUND: Restenosis is a major limitation of coronary angioplasty. Directional coronary atherectomy was developed with the expectation that it would provide better results than angioplasty, including a lower rate of restenosis. We undertook a randomized, multicenter trial to compare the rates of restenosis for atherectomy and angioplasty when used to treat lesions of the proximal left anterior descending coronary artery. METHODS: Of 274 patients referred for first-time, non-surgical revascularization of lesions of the proximal left anterior descending coronary artery, 138 were randomly assigned to undergo atherectomy and 136 to undergo angioplasty; 257 of 265 eligible patients (97 percent) underwent follow-up angiography at a median of 5.9 months. Computer-assisted quantitative measurements of luminal dimensions were determined from the angiograms obtained before and immediately after the procedure and at follow-up. The primary end point of restenosis was defined as stenosis of more than 50 percent of the vessel's diameter at follow-up. RESULTS: Quantitative analysis showed that the procedural success rate was higher in patients who underwent atherectomy than in those who had angioplasty (94 percent vs. 88 percent, P = 0.061); there was no significant difference in the frequency of major in-hospital complications (5 percent vs. 6 percent). At follow-up, the rate of restenosis was 46 percent after atherectomy and 43 percent after angioplasty (P = 0.71). Despite a larger initial gain in the minimal luminal diameter with atherectomy (mean [+/- SD], 1.45 +/- 0.47 vs. 1.16 +/- 0.44 mm; P < 0.001), there was a larger late loss (0.79 +/- 0.61 vs. 0.47 +/- 0.64 mm; P < 0.001), resulting in a similar minimal luminal diameter in the two groups at follow-up (1.55 +/- 0.60 vs. 1.61 +/- 0.68, P = 0.44). The clinical outcomes at six months were not significantly different between the two groups. CONCLUSIONS: The role of atherectomy in percutaneous coronary revascularization remains to be fully defined. However, as compared with angioplasty, atherectomy did not result in better late angiographic or clinical outcomes in patients with lesions of the proximal left anterior descending coronary artery.

Aged↗

PubMed1993

Balloon mitral commissurotomy for mitral restenosis after surgical commissurotomy.

Balloon mitral commissurotomy (BMC) was performed in 113 patients. Of these patients, 27 (24%) (25 women and 2 men, aged 49 +/- 13 years) had recurrent mitral stenosis 13 +/- 6 years (range 5 to 29) after surgical commissurotomy. Eleven patients (41%) were considered at high risk for surgery. BMC resulted in an increase in mitral valve area from 1.1 +/- 0.3 to 1.9 +/- 0.7 cm2 (p < 0.0001), and a decrease in mean mitral gradient from 16 +/- 7 to 6 +/- 3 mm Hg (p < 0.0001). An optimal result of BMC (increase in valve area > or = 25% with a post-BMC valve area > or = 1.5 cm2) was obtained in 18 patients (67%). The results did not differ from those observed in the 86 patients of our entire series without prior surgical commissurotomy. Patients with an optimal result of BMC had a more recent surgical commissurotomy and lesser morphologic alterations of the mitral valve than did those with a nonoptimal result. Patients with echocardiographic scores < 10 had an 80% success rate of BMC; however, this rate decreased to 29% for those with scores > or = 10. One patient (4%) died from a cerebrovascular accident. Clinical follow-up at 1 year showed persistent clinical improvement in 89% of patients with an optimal result of BMC; 72% were in New York Heart Association class I and 17% in class II.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Five- to ten-year outcome after multivessel percutaneous transluminal coronary angioplasty.

The early and late outcome of patients who underwent multivessel percutaneous transluminal coronary angioplasty (PTCA) in a 1-stage procedure are described, and the predictors for clinical event and new revascularization procedure are identified. Of 1,937 patients treated by PTCA between 1981 and 1986, 203 (10.4%) had multivessel PTCA in a 1-step procedure. A follow-up extending to 71 +/- 23 months was obtained in 195 patients (96%). Primary success was achieved in 91% of 494 attempted sites, and complete revascularization in 65% of 203 patients. There were no in-hospital deaths. Acute complications occurred in 13 patients (6.4%), including non-Q-wave (n = 8) and Q-wave (n = 5) infarction, and urgent coronary artery bypass surgery (n = 3). Before PTCA, 126 patients (62%) were in class III or IV of the Canadian Cardiovascular Society classification; at follow-up, 84% were angina-free or in class I. Death occurred in 14 patients and nonfatal myocardial infarction in 18. Angiographic restenosis was diagnosed in 37.2% of dilated lesions in 96 patients (60% of 159 restudied). A repeat revascularization procedure for restenosis or progression of disease, or both, was needed in 92 symptomatic patients (47%). The survival rate at 7 years without the need for surgery or PTCA was 53%, and cardiac survival without myocardial infarction was 85.5%. The only independent predictor of cardiac death was ejection fraction (p < 0.001). The rate of restenosis per patient was primarily determined by the number of segments dilated, whereas progression of disease was related to the number of nonsignificant coronary artery stenoses (< 50%) at baseline (p < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Balloon mitral commissurotomy in patients aged > or = 70 years.

Of 280 patients treated by balloon mitral commissurotomy (BMC) between 1987 and 1991, 28 (10%) were > or = 70 years old. Two patients with associated significant aortic stenosis were excluded from the study. Older patients more often were in New York Heart Association class III or IV (84 vs 67%; p < 0.007) and atrial fibrillation (61 vs 36%; p < 0.0001), and had a higher echocardiographic score (9.3 +/- 2 vs 8 +/- 1.6; p < 0.0004) and a lower baseline cardiac index (2.1 +/- 0.6 vs 2.4 +/- 0.6 liters/min/m2; p < 0.03) than younger ones. Baseline mean pulmonary pressure (37 +/- 11 vs 34 +/- 12 mm Hg), transmitral gradient (14 +/- 4 vs 14 +/- 5 mm Hg) and valve area (1.0 +/- 0.4 vs 1.1 +/- 0.3 cm2) were not different between older and younger patients (p = NS). Acute complications during the procedure (including cardiac perforation, embolism, severe mitral regurgitation and surgical atrial shunt), and 30-day mortality after BMC were more frequent in older than younger patients (27 vs 9% [p < 0.01], and 12 vs 0.8% [p < 0.005], respectively). A complete success, defined as a mitral valve area increase > 25% and postmitral valve area > 1.5 cm2 was obtained in 16 of the 22 older patients (72%) with the completed procedure (compared with 81% of younger ones; p = 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

PubMed1993

Coronary restenosis: evaluation of a restenosis injury index in a swine model.

To investigate the mechanisms of restenosis and detect useful interventions to prevent it, reliable quantitative measurements must be evaluated. Coronary arteries of domestic and minipigs (n = 18) were mechanically injured by balloon overstretching and killed at different intervals (2 to 25 weeks) after quantitative angiographic analysis. Morphometric measurements evaluated intimal hyperplasia at 0.59 +/- 0.42 mm without relation to artery size or balloon/artery ratio. Intimal hyperplasia, expressed as the ratio of neointimal area to total wall area (A), is directly related to the injury, assessed by the ratio of internal elastic lamina (IEL) fracture length to IEL circumference (B), r = 0.84, p = 0.002. Restenosis injury index, defined as A/B, provides a useful tool for the quantitative assessment of future angioplasty-related restenosis interventions.

Angioplasty, Balloon, Coronary↗

PubMed1993

Use of a direct antithrombin, hirulog, in place of heparin during coronary angioplasty.

BACKGROUND: Since the inception of coronary angioplasty, heparin with or without aspirin has been routinely given intraprocedurally to avoid coronary thrombotic complications. Recently, the direct thrombin inhibitor hirulog has been demonstrated to inactivate clot-bound thrombin. The present study was a multicenter dose escalation of hirulog to determine its appropriate dose and feasibility as the sole anticoagulant during coronary angioplasty. METHODS AND RESULTS: At 11 participating centers, 291 patients undergoing elective coronary angioplasty and pretreated with 325 mg aspirin daily were enrolled in sequential groups of intravenously administered hirulog instead of heparin as follows: group 1: bolus, 0.15 mg/kg; infusion, 0.6 mg.kg-1.hr-1 (54 patients); group 2: bolus, 0.25 mg/kg; infusion, 1.0 mg.kg-1.hr-1 (53 patients); group 3: bolus, 0.35 mg/kg; infusion, 1.4 mg.kg-1.hr-1 (44 patients); group 4: bolus, 0.45 mg/kg; infusion, 1.8 mg.kg-1.hr-1 (74 patients); and group 5: bolus, 0.55 mg/kg; infusion, 2.2 mg.kg-1.hr-1 (54 patients). The hirulog infusion was maintained for 4 hours; the primary end point was abrupt vessel closure within 24 hours of the initiation of the procedure. Activated clotting times (ACT) and activated partial thromboplastin times (aPTT) were serially monitored. Abrupt vessel closure occurred in 18 patients (6.2%). By intention to treat, the abrupt closure event rate for groups 1-3 was 11.3% compared with 3.9% in groups 4 and 5 (p = 0.052). There were no significant bleeding complications except for one patient in group 1, who received a two-unit transfusion. A dose-response curve of both ACTs and aPTTs was noted; no coronary thrombotic closures occurred in the small number of patients with ACT > 300 seconds. CONCLUSIONS: The present study documents for the first time that it is possible to perform coronary angioplasty with an anticoagulant other than heparin in aspirin-pretreated patients. Hirulog was associated with a rapid onset, dose-dependent anticoagulant effect, minimal bleeding complications, and at doses of 1.8-2.2 mg/kg, a rate of 3.9% for abrupt vessel closure.

Adolescent↗

PubMed1993

[Short- and mid-term results of percutaneous mitral valve commissurotomy for restenosis after surgical commissurotomy].

Fifty nine of the 280 percutaneous mitral valvuloplasties (21%) performed between March 1987 and December 1991 at the Montreal Heart Institute were carried out for symptomatic mitral restenosis 15 +/- 6 years after surgical commissurotomy. The patients were selected according to echocardiographic criteria. The mitral valve disease was comparable to that of patients without previous surgical commissurotomy. Patients with good hemodynamic result had undergone surgical commissurotomy more recently and had less severe valvular damage than patients with an incomplete (n = 10) or poor result (n = 7). One patient died of a cerebral embolism during the procedure, two patients underwent emergency surgery for a mitral valve rupture and 4 patients had an atrial septal defect with Qp/Qs ratio greater than 1.5 by oximetry. The numbers of successes and complications were comparable to those observed in patients without previous surgical commissurotomy. The patients who had undergone previous surgical commissurotomy were followed up for 1 year. At 12 months, 4 remained in Class II of the NYHA classification, 44 (74%) were improved by at least 1 functional class and 10 (17%) had required a mitral valve replacement. Percutaneous mitral valvuloplasty is therefore a useful procedure in patients with moderate degrees of valvular disease who develop restenosis after surgical commissurotomy. A functional improvement can be expected in 3/4 of patients Complications related to the procedure are rare and acceptable compared with the risks of a second thoracotomy. Failure of percutaneous mitral valvuloplasty is generally due to the degree of valvular disease which contraindicated surgical commissurotomy and required mitral valve replacement.

Adult↗

PubMed1993

Clinical relevance of the low correlations between Doppler and hemodynamic measurements before and after balloon mitral commissurotomy.

The aim of this study was to evaluate the clinical consequences of the poor correlations between Doppler and hemodynamic measurements before and after balloon mitral commissurotomy (BMC). From March 1987 to December 1991, 317 patients with symptomatic mitral stenosis were selected for BMC at the Montreal Heart Institute. Despite the low correlation coefficients between Doppler and hemodynamic measurements before BMC (transmitral gradient: r = 0.57, mitral valve area: r = 0.35, mitral regurgitation: r = 0.33), the positive predictive value of Doppler echocardiography to select patients for BMC was 96%. Hemodynamic success, defined as a final mitral valve area greater than 1.5 cm2 and an increase in mitral valve area of more than 25% was obtained in 204 (80%) of the 253 patients who completed the procedure without complications. Doppler and hemodynamic mitral valve area increase were poorly correlated (r = 0.2) but the sensitivity and specificity of Doppler in the diagnosis of hemodynamic success were 86% and 63% respectively. A prospective six month echocardiography and hemodynamic re-examination was performed in our 50 patients first treated by BMC. Hemodynamic restenosis, defined as a loss of more than 50% of the gain achieved in mitral valve area and a mitral valve area of less than 1.5cm2 were diagnosed in 12 (26%) of the 46 patients with initially successful BMC. Despite a low correlation between Doppler and hemodynamic mitral valve area measurements (r = 0.28), the sensitivity and specificity of echocardiography in the diagnosis of hemodynamic restenosis were 66% and 88% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Long-term (9 to 33 months) echocardiographic follow-up after successful percutaneous mitral commissurotomy.

Late results after successful percutaneous mitral commissurotomy were assessed by prospective clinical and echocardiographic follow-up. Fifty-seven patients were followed for a mean of 19 +/- 6 months (range 9 to 33) after the procedure. Mitral valve area (measured by Doppler half-time method) increased from 1.0 +/- 0.2 to 2.2 +/- 0.5 cm2 immediately after commissurotomy, and then decreased to 1.9 +/- 0.5 cm2 at follow-up (p less than 0.05), whereas gradient did not change after its immediate postcommissurotomy reduction. Echocardiographic restenosis (mitral valve area less than or equal to 1.5 cm2 with greater than 50% reduction of initial gain) was seen in 12 of 57 patients (21%). Atrial shunting, detected by transthoracic color Doppler in 61% of patients immediately after the procedure (color flow jet through atrial septum), persisted in 30% at follow-up. Restenosis by univariate analysis correlated with age, smaller valve area after the procedure, and higher echocardiographic score. Multivariate analysis identified leaflet mobility and calcifications as the components of a score that was predictive for restenosis. Magnitude of shunt (pulmonary-to-systemic flow ratio greater than 1.5), use of a Bifoil balloon (2 balloons on 1 shaft), and smaller valve area after the procedure were predictors by multivariate analysis of the persistence of atrial shunting. Clinical improvement persisted at long-term follow-up (mean New York Heart Association class 1.6 +/- 0.6 vs 2.6 +/- 0.6 before commissurotomy). Improvement of greater than or equal to 1 functional class was seen in 75% of patients (80% of those without and 58% of those with restenosis); patients with a shunt did not differ from the entire group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Methodologic issues in clinical evaluation of stenosis severity in adults undergoing aortic or mitral balloon valvuloplasty. The NHLBI Balloon Valvuloplasty Registry.

Although both catheterization and Doppler measures of valvular stenosis severity have been validated, each has specific advantages and limitations, particularly in the setting of balloon valvuloplasty. Invasive valve area and mean pressure gradient recorded immediately before and after aortic (n = 589) or mitral (n = 608) catheter balloon valvuloplasty were compared with Doppler valve area and mean pressure gradient recorded less than 30 days before and 24 to 72 hours after the procedure. For aortic stenosis, Doppler valve area ranged from 0.1 to 1.4 cm2 before and 0.2 to 2.3 cm2 after catheter balloon valvuloplasty. Doppler and invasive aortic valve areas differed by less than or equal to 0.5 cm2 in 99% and by less than 0.2 cm2 in 92% of patients. Linear correlation was higher before versus after catheter balloon valvuloplasty, for both valve area (r = 0.49 vs r = 0.35, p = 0.01) and mean pressure gradient (r = 0.64 vs r = 0.50, p = 0.01). Group mean invasive valve area was slightly smaller before (0.50 vs 0.59 cm2, p less than 0.0001) but was not different after (0.80 vs 0.78 cm2, p = 0.16) catheter balloon valvuloplasty. Variables affecting the valve area differences were cardiac output, aortic regurgitation, heart rate and blood pressure. Mean pressure gradient differences were related to echo quality, blood pressure and mitral regurgitation. For mitral stenosis, 2-dimensional echocardiographic valve area ranged from 0.4 to 2.8 cm2 before and 0.7 to 3.8 cm2 after catheter balloon valvuloplasty. Two-dimensional echocardiography and invasive mitral valve areas differed by less than or equal to 0.5 cm2 in 96% and by less than 0.2 cm2 in 81% of cases. Linear correlation was not different before versus after catheter balloon valvuloplasty for two-dimensional echocardiographic valve area (r = 0.40 vs 0.36), pressure halftime valve area (r = 0.31 vs 0.32) or mean pressure gradient (r = 0.55 vs r = 0.46). Group mean 2-dimensional echocardiography and pressure halftime valve areas were larger than invasive valve areas before (1.09 vs 1.02 cm2, p = 0.001) and smaller after (1.71 vs 2.02 cm2, p less than 0.0001) catheter balloon valvuloplasty. Important variables affecting the differences were mitral regurgitation, interatrial shunt, cardiac output and heart rate. Nonsimultaneous studies, differing volume flow measurements, and the underlying accuracy of each technique largely account for discrepancies between these methods. The clinical use of each will depend on its ability to predict long-term patient outcome.

Adult↗

PubMed1992

[Immediate and mid-term results of percutaneous pulmonary valvotomy in adults. Apropos of 10 cases].

Percutaneous pulmonary valvulotomy (PPV) is the treatment of choice for isolated congenital pulmonary stenosis of infancy. However, experience with this technique in the adult is much more limited. From November 1983 to November 1990, PPV was performed in 10 adults in our Institute. The mean age was 40 +/- 19 years (range 21 to 71 years). Before PPV, 4 patients were in functional Class II and 6 in functional Class III of the NYHA classification. All procedures were successful with no complications. The right ventricular systolic pressure decreased from 98 +/- 35 to 57 +/- 30 mmHg (p less than 0.01) and the mean pulmonary gradient decreased from 57 +/- 30 to 23 +/- 15 mmHg (p less than 0.01). The cardiac output was unchanged: 5.3 +/- 2.8 and 5.9 +/- 2.6 l/mn (not significant). Pulmonary valve area increased from 0.59 +/- 0.3 to 1.15 +/- 0.5 cm2 (p less than 0.01). The post-dilatation infundibular gradient was less than 10 mmHg in all patients. After an mean follow-up period of 29 +/- 26 months all but one patient (Class II) were in functional Class I. Exercise capacity was 6.9 +/- 2 Mets. Doppler echocardiography indicated a stable mean pulmonary gradient of 16.5 +/- 6.8 mmHg after PPV and 15.0 +/- 7.0 mmHg during follow-up. Pulmonary regurgitation was less than Grade I in all cases. In conclusion, PPV is an effective treatment for adult pulmonary stenosis and carries a low risk. The mid term results are excellent.

Adult↗

PubMed1991

Coronary artery stenting after angioplasty with self-expanding parallel wire metallic stents.

Parallel wire stents were implanted over exchange guide wires at percutaneous transluminal coronary angioplasty sites in 27 canine coronary arteries that were predilated with slightly oversized balloons. Stents were stainless steel, self-expandable, 3.5 to 4.5 mm in diameter, 9 to 12 mm in length, and were made of 10 wires that were longitudinally laser-welded in a zig-zag design. The compressible stent was delivered by the withdrawal of a Teflon outer catheter (4.2 to 4.9F) and the push of a polyethylene inner catheter. Aspirin, 80 mg per day, was given from the day before the study began, and heparin (150 U/kg) was administered during implantation. Quantitative angiography and pathologic examinations were performed at day 0 and at weeks 2, 4, 12, 26 and 52. The coronary angiographic diameter at the stent site immediately after stenting marginally increased from diameter before stenting: 3.22 +/- 0.40 mm versus 3.14 +/- 0.37 mm (p = 0.03), and during a mean of 14 weeks of follow-up, remained unaltered from immediate post-stenting: 3.29 +/- 0.43 mm versus 3.22 +/- 0.40 mm (p = NS) with no stent displacement. Comparisons of patency and thrombosis between heparin-coated and uncoated stents, between left anterior descending and circumflex arteries, and among the three different diameters of stents showed uniformly good results. At microscopy, the wires were oriented perfectly and embedded in the arterial wall, and by 2 weeks they were covered by mucopolysaccharide ground substance, smooth muscle cells, and an almost complete monolayer of neoendothelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗

PubMed1991

Long-term angiographic follow-up after angioplasty of venous coronary bypass grafts.

From April 1981 to June 1987, 57 patients underwent venous coronary bypass graft percutaneous angioplasty and had a minimal follow-up of 18 months. The procedure was elective for 28 patients, urgent for 19, and was considered as an emergency for 10. A total of 64 grafts were dilated that had been bypassed 58 +/- 48 months previously (range 2 to 184 months); lesions were located on the aortic anastomosis in 12 grafts, on the body in 38, and on the coronary anastomosis in 14. Technical success was 95.3% (61 of 64) per lesion; clinical success was 84.4% (54 of 64) per lesion and 82.5% (47 of 57) per patient. Thrombotic complications with images of a lacunar defect occurred in 11 grafts (17.2%). Predictive factors for these complications were: age of grafts 38.5% for greater than 60 month grafts versus 2.6% for less than 60 month grafts (p less than 0.01); site of lesion, body lesion 28.9% versus anastomosis none (p less than 0.01); type of lesion, concentric and short 6% versus other 29% (p less than 0.05); and recent fibrinolysis in 66% versus 10.6% (p less than 0.05). Long-term follow-up is available in the 47 successful patients and the three limited non-Q wave myocardial infarction patients. Two patients died at 13 and 17 months. Long-term angiographic follow-up is available in 45 of 48 patients or 94%. At the end of the study, 35 of 57 (61.4%) venous bypass grafts in 32 patients (64%) were patent after one or more percutaneous transluminal angioplasties.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗

PubMed1991

Percutaneous mitral valvuloplasty in surgical high risk patients.

Among 126 consecutive patients undergoing percutaneous mitral valvuloplasty, 34 were judged to be at high risk for surgery on the basis of age greater than 70 years (n = 13), New York Heart Association functional class IV (n = 11), ejection fraction less than or equal to 35% (n = 3), severe pulmonary hypertension (n = 7), need for associated coronary bypass (n = 4) or additional valve surgery (n = 20) or severe pulmonary disease (n = 3). Baseline features of the high risk group were substantially worse than those of the other patients: age (65 +/- 11 versus 49 +/- 12 years; p = 0.0001) and echocardiographic score (9.4 +/- 1.8 versus 8.2 +/- 1.5; p = 0.005) were higher, whereas cardiac output (2.9 +/- 0.9 versus 4.1 +/- 1.2 liters/min; p = 0.0001) and mitral valve area (0.9 +/- 0.4 versus 1.1 +/- 0.3 mm2; p = 0.002) were lower. Three high risk patients experienced technical failures and three others had major complications. Among the remaining 28 patients, 18 (65%) had a complete hemodynamic success, 4 (14%) an incomplete success and 6 (21%) hemodynamic failure. Stepwise logistic regression analysis retained echocardiographic score as the only factor independently predictive of success. The percent increase in mitral valve area also correlated with echocardiographic score (r = 0.51, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗